Friends and colleagues mourning Klebnikov at St. Catherine the Great Martyr Church on Sunday. Another service will be held Wednesday at Christ the Savior Cathedral.

In the first high-profile murder of a Western journalist in Russia, Paul Klebnikov, the American editor of the new Russian edition of Forbes magazine who for years has relentlessly investigated the dealings of Russia's rich and powerful, was shot dead after leaving work Friday evening.

Klebnikov, 41, was shot four times from a passing car about 100 meters from Forbes' editorial offices on Ulitsa Dokukina in northern Moscow at about 10 p.m.

He was still conscious when Alexander Gordeyev, the editor of the Russian edition of Newsweek, whose offices are in the same building, ran out into the street. Gordeyev said Klebnikov told him he did not recognize the man who shot him and did not know who might have ordered the attack. Klebnikov died shortly after arriving at City Hospital No. 20, Gordeyev said.

It was unclear Sunday whether Klebnikov had received any threats, and his lifestyle suggested he did not feel he was in any danger.

Judging by his letter from the editor in the debut issue of Forbes Russia in April, Klebnikov seemed to believe that Russia had changed. He wrote that the readiness of the Russian market for such a publication was "one sign that Russian business has reached a new, more civilized stage of development."

Investigators as well as Klebnikov's colleagues and friends said they had little doubt the murder was directly related to his journalistic work.

"Paul was a very independent journalist, was very professional and always spoke the truth. And there is no question that he died for speaking the truth," Boris Jordan, former general director of NTV television and a personal friend of Klebnikov's, said after a memorial service Sunday at St. Catherine the Great Martyr Church in central Moscow.

Colleagues and friends, however, were not ready to speculate on whether the murder was more likely to be related to investigations by Forbes Russia -- which in May published a list of Russia's 100 richest people, some of whom were unhappy about the publicity, given the current anti-oligarch mood -- or to Klebnikov's other projects, which have delved into the darker side of Russia's political and business elite.

One such investigation led to an article in Forbes in 1996 on Boris Berezovsky, who at the time was a Kremlin insider. The article called Berezovsky a "powerful gangland boss" and accused him of ordering the 1995 murder of television journalist Vladislav Listyev. Berezovsky said the article consisted of a "series of lies" and sued the magazine in Britain.

Klebnikov, however, persisted and followed up the article with a book titled "Godfather of the Kremlin: Boris Berezovsky and the Looting of Russia."

Berezovsky withdrew the libel suit last year after Forbes acknowledged that there was no evidence that he had ordered the murder of Listyev or anyone else.

In a telephone interview over the weekend, Berezovsky said Klebnikov led a dangerous life.

"Somebody clearly did not like the way he operated and decided to sort it out with him, Russian-style, not through the English courts like I did," Berezovsky said.

"Klebnikov was like a bull in a china shop. ... All over the world rich people like to keep a low profile," he said. But in Russia, he said, the situation was even more extreme. "If you publish a list of the country's richest people, it's like informing on them to the prosecutors. Standards are different."

Berezovsky said Klebnikov may also have stepped on some toes in the Kremlin.

An investigative piece published in Forbes Russia in April looked into connections between Surgutneftegaz and the firm Kinex, which is one of the traders for the oil major's exports. Kinex, according to Hermitage Capital Management, for years has been benefiting from lucrative contracts to export Surgut oil. One of Kinex's alleged beneficiaries, Gennady Timchenko, was earlier this year labeled as the manager of President Vladimir Putin's personal fortune by unsuccessful presidential candidate Ivan Rybkin, which is likely to have prompted Forbes' investigation. Rybkin's presidential run was funded by Berezovsky.

"Klebnikov touched on the most sensitive issues. He raised questions about ... those that are sitting at the top of Putin's business. Putin may not have liked this as it touched on his closest circle," Berezovsky said.

According to friends and colleagues, Klebnikov was also nurturing a sequel to the book about Berezovsky. Due to Klebnikov's reluctance to share much about his work in progress, it was difficult to establish Sunday whether he had begun writing it, or whether it was to be focused on Berezovsky or any other members of Russia's political and financial elite.

Irina Silayeva, general director of Axel Springer Russia, which publishes the Russian edition of Forbes, said Klebnikov's co-workers did not notice any signs that his life was in danger as a result of his work as editor of the magazine.

"There was no basis for any attack based on what was printed," she said. "It is very difficult to comment. This came as a complete shock to me. Paul was a very talented person, but if he was working on something, he would not share that he was doing so with anyone."

Klebnikov's death will not affect the future of the magazine, which will continue to be published, Silayeva said.

Forbes Russia publisher Leonid Bershidsky agreed. "I would not like for the magazine to close. The news should continue. Paul would have wanted this," he said.

Klebnikov's murder sent shivers through the Moscow journalistic community. It can only be matched by the murders of American hotelier Paul Tatum in 1996, journalist Dmitry Kholodov in 1994 and Listyev in 1995, none of which has been solved.

"Russia is consistently one of the world's most dangerous places to be a journalist and we call on the Russian authorities to aggressively investigate and prosecute this case," Ann Cooper, executive director of the Committee to Protect Journalists, said in a statement.

At least 14 journalists have been killed in Russia in connection with their work since 2000, and none of their killers has been brought to justice, CPJ said.

"This shameful record of impunity is one of the reasons these murders continue to happen," Cooper said. "It sends a chilling message to Russian journalists and a terrible message to the rest of the world about the Kremlin's indifference to press freedom."

Klebnikov did not appear to be concerned about safety, his friends and colleagues said. Since moving to Moscow earlier this year, he had used public transportation to get around. His wife and three children visited him as recently as last week, which suggests he was not particularly worried, Jordan said.

No date has been set for the funeral, which is expected to take place in New York, where Klebnikov, a descendant of emigres who fled Russia after the 1917 Revolution, was born and raised. Another memorial service is to be held in Moscow at 2 p.m. Wednesday at the lower church of the Christ the Savior Cathedral.

Klebnikov is survived by his wife, Musa; sons Alexander, 12, and Grigory, 7; daughter Sophia, 4; and two brothers, Peter and Michael.